2. Why is the text running from left to right and not from right to left? What I have heard (or rather read I guess) regarding our own system, the cause is due to most people being right handed.

Writing with your right hand it is better to write from left to right so that it will be more easy to see what you have written. Furthermore, in earlier times when using a pen you avoided brushing out what had been written before the ink had dried.

This type of explanation cannot be used also for the rongorongo system of writing. For one thing they incised the glyphs on their wooden tablets with a shark's tooth.